Preheat an outdoor grill for medium-high heat, and lightly oil the grate. Place the skewers into a basin of water and allow to soak while you prepare ingredients.
Slather the salmon on both sides with 1/4 cup of barbecue sauce, and set aside.
Place mango, red bell pepper, peach, and pineapple chunks into a bowl. In a small bowl, stir 3 tablespoons of barbecue sauce with water, lime juice, olive oil, and honey until well mixed; pour the dressing over the fruit and pepper chunks, and toss to coat.
Thread skewers with alternating pieces of mango, red bell pepper, peach, and pineapple chunks.
Grill the skewers on the preheated grill, turning every few minutes, until each side of the skewered fruit is browned, about 10 minutes. Move the fruit skewers to a cool part of the grill, and place the salmon fillet onto the hot grill surface, skin side down. Grill the fish until it shows brown grill marks, the fish is opaque, and the flesh flakes easily, 6 to 8 minutes per side. Serve grilled salmon with fruit skewers.